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1.
In 10 newborn Holstein calves, which were initially bottle-fed on pooled colostrum, there were transient increases in several serum enzymes. Within a few hours, the mean serum gamma-glutamyl transferase (gammaGT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), acid phosphatase (ACP), and lactate dehydrogenase (LDH) activities increased 62.5, 2.4, 2.0, 1.8 and 1.3 fold, respectively. In two other calves given initial feeds of enzyme-free pasteurized milk, there were similar increases in serum enzymes, except serum gammaGT. Correct interpretation of serum enzyme activities in newborn calves must take into account the normal increases which occur after feeding colostrum. Serum gammaGT was the only enzyme to increase markedly as a result of its absorption from colostrum. The other serum enzymes are presumably released from the tissues of the calf. The increased activities of serum CK observed in some newborn calves probably resulted from trauma during birth or increased muscular activity after birth.  相似文献   

2.
Consumption of a second meal of colostrum with high quality could contribute to the intestinal epithelium development, especially if there is poor supply of colostrum just after birth. The effect of a second colostrum meal was evaluated on histomorphometry of the intestinal mucosa of newborn Holstein calves fed with high‐ and low‐quality first colostrum. Seventy‐two calves were fed with a first colostrum meal with high (HFM, close to 100 mg/ml) or low (LFM, close to 30 mg/ml) IgG concentration. At 12 hr of life, three treatments of second colostrum feeding were applied to the calves either fed high or low first colostrum: calves fed with low (LOW—close to 30 mg/ml) or high (HIGH—close to 100 mg/ml) IgG concentration; and colostrum enriched with lyophilized bovine colostrum with high IgG concentration (ENRICHED—higher than 120 mg/ml), resulting in six groups. Intestinal samples were collected after 24 and 72 hr of life. In the distal jejunum and ileum, LOW showed higher villus height than ENRICHED (p < .05). In the distal jejunum, greater villus perimeter was observed in the LOW compared to ENRICHED at 24 hr (p < .05). In ileum, LFM showed higher villus perimeter compared to HFM (p < .05). LOW showed the highest villus height‐to‐crypt depth ratio in the medium and distal jejunum and ileum, p < .05. ENRICHED and HFM showed decreased muscle layer thickness in the proximal and distal jejunum respectively (p < .05). The results reveal that the high concentration of total solids, crude protein, IgG and IGF‐I of colostrum with high quality worsened the absorptive area, but may have stimulated the activity of cell division in intestinal crypts. Considering the present results, bovine colostrum enriched with lyophilized bovine colostrum stimulates intestinal epithelium renewal of Holstein calves in the first days of life.  相似文献   

3.
OBJECTIVE: To determine the amount of colostral IgG required for adequate passive transfer in calves administered colostrum by use of oroesophageal intubation and evaluate the impact of other factors on passive transfer of colostral immunoglobulins in calves. ANIMALS: 120 Holstein bull calves. PROCEDURES: Calves were randomly assigned to specific treatment groups on the basis of volume of colostrum administered and age of calf at administration of colostrum. Colostrum was administered once by oroesophageal intubation. Equal numbers of calves received 1, 2, 3, or 4 L of colostrum, and equal numbers of calves received colostrum at 2, 6, 10, 14, 18, or 22 hours after birth. Serum samples were obtained from calves 48 hours after birth for IgG determination by radial immunodiffusion assay. Effects of factors affecting transfer of colostral immunoglobulins were determined by use of a stepwise multiple regression model and logistic regression models. RESULTS: A minimum of 153 g of colostral IgG was required for optimum colostral transfer of immunoglobulins when calves were fed 3L of colostrum at 2 hours after birth. Substantially larger IgG intakes were required by calves fed colostrum > 2 hours after birth. CONCLUSIONS AND CLINICAL RELEVANCE: Feeding 100 g of colostral IgG by oroesophageal intubation was insufficient for adequate passive transfer of colostral immunoglobulins. At least 150 to 200 g of colostral IgG was required for adequate passive transfer of colostral immunoglobulins. Use of an oroesophageal tube for administration of 3 L of colostrum to calves within 2 hours after birth is recommended.  相似文献   

4.
The fate of colostrum and other fluids given with an oesophageal feeder was studied in newborn calves and in young calves up to 3 weeks by means of radiological techniques. Any fluid given with an oesophageal feeder was found in the forestomachs, since it apparently did not induce an oesophageal groove reflex. Also when suckling was induced during feeding with the oesophageal feeder, the oesophageal groove reflex did not occur. The outflow of colostrum and other fluids from the forestomachs to the abomasum and small intestine occurred for the most part within 3 hours. Only the emptying of the ventral ruminal sac was sometimes delayed for 24 or 48 hours.

The results obtained in calves up to 3 weeks old did not differ from those obtained in newborn calves.

It was concluded that although colostrum given by oesophageal feeder entered the forestomachs, the rapid flow to the abomasum and small intestine created the conditions for a sufficient absorption of immunoglobulins. Application of colostrum with an oesophageal feeder in newborn calves promises to be a timesaving and effective method for creating an optimum passive immunity of the calves.  相似文献   

5.
Newborn calves were subjected to cold stress and made hypothermic by immersion in water at 15 to 17 degrees C. Cold stress delayed the onset and significantly decreased (P less than 0.05) the rate of absorption of immunoglobulins (IgM, IgG1 and IgG2) up to 15 hours after first feeding of pooled colostrum. However, the net absorption of colostral immunoglobulins was not affected. The possible deleterious effect of cold stress on absorption of colostral immunoglobulins by newborn calves under range conditions is discussed.  相似文献   

6.
Different methods for the dry preservation of colostrum to be used as a total replacement for bovine colostrum were evaluated. Pooled colostrum from the first and second postpartum milkings from multiparous dairy cows containing immunoglobulin in excess of 40 g/L was freeze-dried, microwave vacuum evaporated, and spray-dried. Spray-drying produced a dried colostrum in which immunoglobulin quantity and function were preserved and was the most cost-effective. Other dehydration methods, although effectively conserving immunoglobulins, were too slow and costly to be used to produce a bovine colostrum replacer. Newborn, colostrum-deprived, dairy calves fed spray-dried colostrum containing 126 grams of immunoglobulin reconstituted in three liters of water as their sole source of immunoglobulin achieved normal mean serum immunoglobulin concentrations. Spray-dried colostrum with high concentrations of immunoglobulin may be produced economically and used as an effective and convenient colostrum replacer in newborn calves.  相似文献   

7.
Three main factors underlying the immunity state of newborn calves are evaluated. During the absorption of colostral immunoglobulins the immunoprotein profile of a newborn calf is influenced by the following factors (arranged according to importance): volume of the first colostrum taken in, time of the first drinking, and immunoglobulin concentration (IgG and IgM) in colostrum. When given 1.1 or 2.0 litres of colostrum of about the same quality (as to immunity), the calves of the compared groups had significantly different levels of total serum Ig measured 24 hours after birth: 10.7 and 18.6 U ZST (P less than 0.05) and 48 hours after birth: 11.7 and 19.7 U ZST (P less than 0.01). A significant difference in total serum proteins was observed only in the 48th hour post partum (54.4 and 63.6 g per litre; P less than 0.05). At the intake of 1.5 litres of colostrum within two and five hours after birth, with the same total intake of the sum of IgG and IgM in the groups, the calves exhibited, in the 24th hour, total serum Ig levels of 14.4 and 12.4 U ZST (P greater than 0.05) respectively, and 56.0 and 47.9 g per litre (P greater than 0.05) of total serum protein, respectively. With a different concentration of colostral IgG (122.0 or 77.0 g per litre) the statistically significant Ig absorption into blood was adequately different (17.2 and 10.0 U ZST, respectively, P less than 0.05). The differences in the concentration of total serum Ig and total proteins between the 24th and 48th hour after birth were only very small and statistically insignificant. Regression analysis proved a significant relation (P less than 0.01) between the level of total serum Ig 24 and 48 hours after birth and the total amount of IgG and IgM taken in with the first colostrum. The calves coming from primiparae had a lower immunity (P less than 0.01) in comparison with the calves of multiparae. A similar relation in the absorption of colostral Ig was observed when the spontaneously born calves were compared with those born by the Caesarean section (P less than 0.01).  相似文献   

8.
Comparison of three methods of feeding colostrum to dairy calves   总被引:4,自引:0,他引:4  
Absorption of colostral immunoglobulins by Holstein calves was studied in 3 herds in which 3 methods of colostrum feeding were used. Failure of passive transfer, as determined by calf serum immunoglobulin G1 (IgG1) concentration less than 10 mg/ml at 48 hours of age, was diagnosed in 61.4% of calves from a dairy in which calves were nursed by their dams, 19.3% of calves from a dairy using nipple-bottle feeding, and 10.8% of calves from a dairy using tube feeding. The management factor determined to have the greatest influence on the probability of failure of passive transfer in the herds using artificial methods of colostrum feeding (bottle feeding or tube feeding) was the volume of colostrum fed as it affected the amount of IgG1 received by the calf. In dairies that used artificial feeding methods, failure of passive transfer was infrequent in calves fed greater than or equal to 100 g IgG1 in the first colostrum feeding. In the dairy that allowed calves to suckle, prevalence of failure of passive transfer was greater than 50% even among calves nursed by cows with above-average colostral IgG1 concentration. Analysis of the effect of other management factors on calf immunoglobulin absorption revealed small negative effects associated with the use of previously frozen colostrum and the use of colostrum from cows with long nonlactating intervals.  相似文献   

9.
Twenty-seven newborn Holstein bull calves were bottle-fed 2 litres of pooled colostrum which had been stored at -20 degrees C. Blood gas analysis before feeding showed a partially compensated respiratory acidosis in most of the calves, although they all appeared to be clinically normal. Mean venous blood pH was 7.346, carbon dioxide tension (PCO2) was 57.5 mmHg (7.6 kPa), bicarbonate was 30.6 mmol/l and base excess was 3.82 mmol/l. Mean serum IgG1 increased to 8.1 g/l after feeding colostrum. Several significant positive correlations were observed between post-absorptive serum protein, IgG1, IgM, gamma-glutamyltransferase (gamma GT) and D-xylose. Calves with either low serum albumin, high serum CK or low serum gamma GT before feeding tended to have less absorption of colostral protein. It was concluded that reduced absorption of IgG1 from colostrum is associated with hypercapnia in apparently healthy newborn calves.  相似文献   

10.
Abstract

AIMS: To describe colostrum quality in spring-calving dairy herds in New Zealand, in terms of Brix, pH and total and coliform bacterial counts and to investigate associations between farm management practices and these measures of colostrum quality.

METHODS: In June 2015, commercial dairy farms (n=105), located in North and South Islands of New Zealand, were visited shortly after the first cows had calved, and when approximately 50% and 80% of the herd had calved (early, middle and late visits). One litre of pooled colostrum that was being fed to newborn calves was collected at each visit and used to determine Brix, pH, total bacterial and coliform counts. A survey of calf management practices was conducted with the herd manager or calf rearer after the final visit.

RESULTS: Of 298 pooled colostrum samples tested 29/298 (9.7%) had Brix >22%. Brix was higher on farms where calves were picked up twice daily compared with once daily (18.2 (95% CI=16.5–19.9)% vs. 15.9% (95% CI=15.2–16.6)%; p=0.012), and was lower where first milking colostrum was combined with colostrum obtained at later milkings (15.0 (95% CI=13.9–16.1)%) compared with where it was not (16.9 (95% CI=16.3–17.6)%; p=0.002). Vaccination of all cows against calf diarrhoeal pathogens was associated with increased Brix compared with no vaccination (18.1 (95% CI=16.6–19.6)% vs. 16.3 (95% CI=15.6–17.0)%; p=0.033). Mean pH of samples tested decreased from 5.97 (95% CI=5.84–6.09) to 5.58 (95% CI=5.45–5.71) for early and late-season visits, respectively (p<0.001). Of 268 samples tested, 23 (8.6%) had bacterial counts below the recommended threshold of 1.00×105 cfu/mL. Mean bacterial counts increased from 2.75 (95% CI=1.80–3.70)×108 to 4.99 (95% CI=3.95–6.03)×108 cfu/mL for early and late-season visits, respectively (p<0.001). Of 259 samples tested, 23 (8.9%) had coliform counts below the recommended threshold of 1.00×104 cfu/mL.

CONCLUSIONS AND CLINICAL RELEVANCE: On a large majority of dairy farms included in this study the pooled colostrum fed to newborn calves had sub-optimal Brix and excessive bacterial counts. Farm-level risk factors such as twice daily pick up of calves from the paddocks, herd vaccination and feeding pooled colostrum that did not combine colostrum obtained at later milkings with first milking colostrum were associated with colostrum quality measures.  相似文献   

11.
OBJECTIVE: To examine the effects of curd formation within the abomasum, on the absorption of gamma glutamyl transferase (GGT) from colostrum in newborn calves. DESIGN: An in vivo physiological study with controls, and in vitro examination of calf abomasal fluid. PROCEDURES: Newborn calves were taken from cows without allowing them to suckle. They were fed either 1.5 kg colostrum or 1.5 kg colostrum plus rennet, with intervals between calving and colostrum feeding ranging from 0.4 to 12.7 h. Absorption of proteins from the whey component of colostrum was assessed from the rise in activity of serum GGT. In in vitro studies, colostrum was incubated with bovine amniotic fluid, newborn calf abomasal fluid or newborn calf forestomach contents, with or without rennet, to test the curd inhibiting effects of components in the abomasal fluid of newborn calves. RESULTS: In vivo: addition of rennet to the colostrum feed reduced the proportion of calves with serum GGT activity below 500 U/L by 60%. In vitro: 43% of newborn calves lacked curd forming activity in their abomasal fluid, and that deficiency was corrected by adding rennet to the incubation medium. CONCLUSIONS: Some calves are born with low amounts of curd forming enzyme activity in the abomasum. This may compromise their ability to absorb large whey proteins from the first feed of colostrum. Adding rennet to the first colostrum feed may improve passive immunity in those calves.  相似文献   

12.
Various systems of early post natal management of the newborn calf were examined to determine which would consistently achieve high serum concentrations of maternally derived immunoglobulins, and to examine the factors which might influence this transfer. Early assisted sucking of colostrum to satiation produced consistently high serum concentrations of absorbed immunoglobulins with a mean of 27.17 +/- 8.92 zinc sulphate turbidity (ZST) units for 100 calves. No significant increase in the serum concentrations of absorbed immunoglobulins occurred when calves, which had been assisted to suck immediately after birth, were permitted to remain with their dams and encouraged to suck again at 12 hours (29.20 +/- 9.40 ZST units). Despite early assisted sucking, a small proportion of calves may remain hypogammaglobulinaemic because of the low concentration of immunoglobulins in their dams' colostrum; leakage of colostrum from the udder before calving was the major cause of these low immunoglobulin concentrations. A highly significant correlation was demonstrated between the colostral immunoglobulin concentrations and the passively acquired serum immunoglobulin concentrations of the calves. With this intensive system of early assisted sucking the breed of the calf did not significantly influence the absorption of colostral immunoglobulins.  相似文献   

13.
Introduction Newborn development is characterized by high protein synthesis and nitrogen (N) turnover rates in many tissues, especially in the gastrointestinal (GI) tract (G oldspink and K elly 1984; Y oung et al. 1988; S immen et al. 1990; X u 1996). Colostrum provides particularly large amounts of nutrients (especially proteins) and immunoglobulins as well as non-nutrient growth-promoting factors; it therefore plays a major role in the development of the neonatal gut, especially protein synthesis, and other organs, as shown in several species including cattle (B erseth et al. 1983; P atureau M irand et al. 1990; C ampana and B aumrucker 1995; O dle et al. 1996; X u 1996; B urrin et al. 1997). Rates of body protein synthesis and N turnover were greater during enteral than during parenteral feeding, indicating considerable involvement of the GI tract in protein metabolism (D uffy and P encharz 1986). Protein components in colostrum provided about 35% of amino acids (AA) in newborn lambs, suggesting that amounts of ingested protein with colostrum greatly influence the AA status of the neonate (Y von et al. 1993). Glutamine and glutamate are the most abundant AA in bovine milk protein (M eijer et al. 1993) and glutamine is of special interest for postnatal gut development (S ouba 1991; K imura 1996; H eird 1998). The glutamine:glutamate ratio was markedly changed in neonatal calves (D emign & eacute ; and R& eacute ; m & eacute ; sy 1979) after colostrum intake. Recently, we have demonstrated that gut growth and absorptive capacity of the intestine, as well as metabolic and endocrine changes in newborn calves, are greatly dependent on amounts of ingested colostrum (H ammon and B lum 1997, 1998; B& uuml ; hler et al. 1998). Based on that AA absorption, metabolism and status may be influenced by amounts of fed colostrum. Therefore in this study we have tested the hypothesis that feeding colostrum for different durations, or feeding only milk replacer, affects plasma protein and free AA concentrations during the first week of life in calves.  相似文献   

14.
We investigated the relationship of the stress levels of the dam before and after delivery to that of her offspring soon after birth. Eight pregnant cows were penned 7 days before calving. Blood was taken from the jugular vein of cows at ?7, 1, 2 and 3 days from calving. Blood was also taken from newborn calves at 6 h and 1 and 2 days after birth. Concentrations of cortisol and immunoglobulin G in blood and colostrum were examined. Pearson's correlation coefficient showed that the higher the plasma cortisol concentration of a cow before calving, the higher that of its calf after birth (all P < 0.01). In addition, path analysis demonstrated that the direct effect of the plasma cortisol concentration of the dam before calving on the plasma cortisol concentration of her calf after birth was 0.971 (P < 0.01). However, the colostrum cortisol concentration correlated with neither plasma cortisol concentrations of cows before calving nor that of calves after birth. Unlike cortisol, a clear correlation of immunoglobulin G concentrations in plasma and colostrum was not observed between cows and calves. The results indicate stress is transferred from a cow to her newborn calf not by way of the colostrum but through the placenta.  相似文献   

15.
Colostrum-replacement products are an alternative to provide passive immunity to neonatal calves; however, their ability to provide adequate levels of antibodies recognizing respiratory viruses has not been described. The objective of this study was to compare the serum levels of IgG at 2 d of age and the duration of detection of antibodies to bovine viral diarrhea virus 1 (BVDV-1), bovine viral diarrhea virus 2 (BVDV-2), bovine respiratory syncytial virus (BRSV), bovine herpesvirus 1 (BHV-1), and bovine parainfluenza virus 3 (BPIV-3) in calves fed maternal colostrum (MC) or a colostrum replacement (CR) at birth. Forty newborn male Holstein calves were assigned to the CR or the MC group. Group CR (n = 20) received 2 packets of colostrum replacement (100 g of IgG per 470-g packet), while group MC (n = 20) received 3.8 L of maternal colostrum. Blood samples for detection of IgG and virus antibodies were collected from each calf at birth, at 2 and 7 d, and monthly until the calves became seronegative. Calves in the MC group had greater IgG concentrations at 2 d of age. The apparent efficiency of absorption of IgG was greater in the MC group than in the CR group, although the difference was not significant. Calves in the CR group had greater concentrations of BVDV neutralizing antibodies during the first 4 mo of life. The levels of antibodies to BRSV, BHV-1, and BPIV-3 were similar in the 2 groups. The mean time to seronegativity was similar for each virus in the 2 groups; however, greater variation was observed in the antibody levels and in the duration of detection of immunity in the MC group than in the CR group. Thus, the CR product provided calves with more uniform levels and duration of antibodies to common bovine respiratory viruses.  相似文献   

16.
Concentrations of immunoglobulins and total proteins in second-day post-partum serum samples of 62 beef calves from multiparous dams were measured by zinc sulphate turbidity, electrophoresis, radial immunodiffusion and refractometry. These results, together with health records and weight gains, were used to evaluate the practice of routinely force-feeding 1 L of stored colostrum to suckled beef calves immediately after birth. There was no apparent benefit from such force-feeding. It did not result in greater 48-hour serum immunoglobulin levels, nor did it improve weight gains at 42 days. None of the calves required treatment for neonatal disease, but one force-fed calf died from inhalation of regurgitated colostrum.  相似文献   

17.
This study compared serum immunoglobulin G (IgG) concentrations in calves fed colostrum with those of calves fed a colostrum supplement containing spray-dried serum. Twenty-four Holstein calves were randomly assigned to I of 2 treatment groups (fresh colostrum or colostrum supplement). Each calf was fed 4 L of colostrum (n, = 12) or 4 L of colostrum supplement (n2 = 12) via oroesophageal intubation at 3 hours of age. The concentration of the colostrum supplement fed to calves was twice the manufacturer's recommendation. The median and range values for colostral IgG concentration were 6,430 mg/dL and 1,400-17,000 mg/ dL, respectively. Median serum IgG concentrations at 2 days of age differed significantly (P = .001) between calves receiving fresh colostrum (3,350 mg/dL) and the colostrum supplement (643 mg/dL). Eight percent of calves force fed colostrum had serum IgG concentrations < 1,000 mg/dL, whereas 75% of calves force-fed supplement had IgG concentrations below this threshold. The calculated population relative risks for mortality associated with passive transfer for calves force-fed colostrum and calves force-fed colostrum supplement were 1.09 and 1.90, respectively. Force-fed fresh colostrum is superior to the colostrum supplement studied, but the colostrum supplement has similar efficacy to routine colostrum administration practices.  相似文献   

18.
The aim of the study was to evaluate the influence of soybean trypsin inhibitor (TI) on immunoglobulin G (IgG) serum levels and growth in neonatal goat kids. Twenty‐four newborn kids were fed with natural colostrum (group A), and 24 kids received the same colostrum with 1 g of TI per litre (group B). Blood samples were obtained at birth and on days 1, 2 and 4 of life to analyze serum proteins, IgG and haematological parameters. There were no clinical signs of disease and no significant differences in body weight between the groups. Haematological parameters were not affected by treatment. The peak of serum IgG was reached at 24 h of life, but no effects of soybean TI was observed on serum IgG levels. The apparent efficiency of absorption of IgG was similar in both groups (group A 24.5% vs. group B 25.2%, p > 0.05). The addition of TI to colostrum did not change the concentration of serum proteins and their fractions in goat kids. The correlation between serum IgG and γ‐globulin was positive and significant (p < 0.01, r = 0.64) in group A, but not in group B (p > 0.05, r = 0.08), suggesting a negative influence of soybean TI on γ‐globulin absorption. These results show that addition of soybean TI to colostrum did not improve the performance or immunological status in goat kids.  相似文献   

19.
Subclinical ketosis of dry cows was studied as to its effect on the composition of colostrum and on the health condition and selected clinico-biochemical parameters in the new-born calves of these cows. The experimental group consisted of eight cows with ketonuria and their calves. The control group consisted of six cows without ketonuria and their new-born calves. Calves of both groups were reared in similar conditions. Colostrum samples were taken from the first milking and then from the milking 24 hours after parturition. The blood of the calves was sampled before the intake of colostrum and 24 hours after birth. The concentration of ketone bodies, particularly beta-hydroxybutyrate, was much higher in the colostrum of both groups of cows than in the blood (62.6 mg total ketone bodies per 1 litre of the first colostrum of the cows of the experimental group). The concentration of ketone bodies slightly increased after parturition. The cows with ketonuria secreted into colostrum a larger amount of oxidated ketone bodies. Colostrum quality was good in both groups. Decreased viability was not recorded during the clinical examination of the calves after birth. The level of total ketone bodies in the blood of pre-colostral calves in the experimental group was 10.4 mg per litre (a much lower concentration than in blood of their dams), and exhibited no appreciable change after taking in the colostrum. The blood of calves born to cows with ketonuria contained significantly higher amounts of oxidated ketone bodies. No correlation was demonstrated between the contents of ketone bodies in the blood of cows, in the blood of calves, and in the colostrum. The calves of the experimental group were found to have a significantly higher AST activity in plasma, as compared with the control group. Twenty-four hours after birth, the quantity of immunoglobulins in the blood serum was significantly lower in the calves of the experimental group. Thanks to good attendance and hygiene, the morbidity did not increase and no losses occurred.  相似文献   

20.
An insufficient absorption of colostrum-immunoglobulins (Ig) by the newborn calf may result in morbidity and mortality at the early age of 1-2 weeks after birth. According to a study from California, such losses amounted to 20% in dairy herds. Ig-deficiencies were observed in almost 90% of all calves which died within the first week of their lives. The rapid identification of Ig-deficient calves, compensation by feeding colostrum from another dam or the application of relevant commercial products from the dairy industry are attempts to remedy such a situation. Feeding bovine colostrum to lambs, kids, foals and piglets, bovine Ig is readily absorbed into the blood-system of these animals. Vaccination of pregnant animals aims at the provocation of specific antibodies for the protection of the offspring. The application of the vaccine into the mammary gland at ablactation provokes specific IgA- and IgM-antibodies which are normally not channelled from the blood system + of the mother into the colostrum. The advantage of the vaccination of pregnant animals is the immediate provision of protecting antibodies for the newborn immuno-incompetent animal. Under the pressure of an increasing criticism against the routinely applied supplementary feeding of antibiotics, this kind of immunization may reach more and more of importance. Like non-specific Igs, specific colostrum-Igs are absorbed into the blood-system of newborns from other animal species.  相似文献   

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